Photo: Didier Duforest; May 2007; (Decauville N°1652 de 1916)
This “Decauville 8T” is an 0-6-0T locomotive that was specifically produced for the French army trench railways during WWI to their ‘standard gauge‘ of 600mm ((1 ft 11 5/8 in). Decauville produced 320 of these locomotives, with both well and side tanks between 1914 and 1918. Decauville could not keep up with the military's demand, so Kerr Stuart of the UK built a further 70 units. The KS locomotives were known as the "Joffre" class. A further, somewhat different class, the "Haig" class was produced by Kerr's from what were ostensibly excess parts.As a historical point the original four locos built by Kerr Stuart had to be modified on shipping to France. The tyre profile was altered, as was the springing, for those four, and for all the later production. Subsequently an additional “ballast” weight was added behind the front buffing plate.
A number of these locomotives still exist; Axe on the rebuilt L&B is a modified Joffre, thus proving that despite being built for a short term life, they were rugged and reliable.
The Photo Tool is for a War Department Decauville 8T 0-6-0T and is not a complete model. These are a set of parts to aid to scratch building.These parts could be used to scratch build a Kerr Stuart "Joffre" class as well, as the differences were cosmetic and were related to the well tank, and as noted above, the springing, tyre profile, and a few other incidentals.
Photograph: Bruno Duchesne; Line Drawing: public domain draughtsman unknown